Describing a Red Blood Cell Population Using RBC Indices and Red Cell Distribution Width

Author: Sheryl A. Whitlock, MA.Ed, MLS(ASCP)BB
Reviewers: Joshua J. Cannon, MS, MLS(ASCP)CMSHCM and Rory Huschka, M.Ed., MLS(ASCP)
See all available Compliance & CE courses »

Continuing Education Credits

P.A.C.E.® Contact Hours: 1 hour(s)

Florida Board of Clinical Laboratory Science CE Credit Hours

Florida Board of Clinical Laboratory Science CE - General (Hematology): 1 hour(s)

(based on 637 customer ratings)

This course discusses the use of red cell indices and red cell distribution width to describe a population of red blood cells. The course provides information regarding interpretation of red cell histograms that are part of the automated cell count and correlations between indices, RDWs, and peripheral blood smear observations.

Objectives

  • Identify red blood cell (RBC) indices reported by automated cell counters.
  • Correlate observed RBC morphology to red cell indices reported by automated cell counters.
  • Apply red cell distribution data to the RBC population observed on the peripheral smear.
  • Correlate measured RBC indices to anemias.
  • Discuss the significance of delta checks in relation to RBC indices.

Course Outline

  • Definitions, calculations, and red cell distribution histogram interpretations
    • Red Blood Cell (RBC) Indices: Definitions and Calculations
    • Table Summary: Red Blood Cell Indices
    • Red Blood Cell Distribution Width (RDW): Definition and Calculation
    • Red Blood Cell Distribution Width (RDW): Definition and Calculation, continued
    • Interpretation of Red Blood Cell (RBC) Histograms
    • Interpretation of Red Blood Cell (RBC) Histograms, continued
    • The hematology laboratory is experiencing instrument downtime. The laboratory has a backup method for hemoglobin and hematocrit testing that is used until the instrument is repaired. The hematologist calls and asks if you can provide any red blood cell indices. Which of the indices, if any, can you provide to the hematologist?
    • Which of the following formulas will provide the value that reflects the average cell volume in a blood sample?
    • A complete blood count is performed. The white blood cell count is elevated and requires a manual differential. The medical laboratory scientist evaluates the red blood cell size, size variation, and morphology and finds it normal. Which of the following histograms would represent this red blood cell morphology?
    • A medical laboratory technician is evaluating a blood smear and notices variability in cell size. Which parameter from the automated blood count would confirm the anisocytosis observed on the blood smear?
    • Each statement describes a population of RBCs measured on a peripheral blood smear. Choose the appropriate RBC histogram for each red blood cell population. The diameter of a normal RBC is approximately 6–8 µm. A normal red cell distribution curve is shown on the right.
  • Red blood cell morphology correlated with automated measured and calculated parameters
    • Red Blood Cell (RBC) Size Variation
    • Red Cell Distribution Width (RDW) Correlated with Peripheral Smear
    • Red Cell Distribution Width (RDW) Correlated with Peripheral Smear, continued
    • Red Blood Cell (RBC) Color Variation
    • RBC Size and Color Descriptions
    • Red Blood Cell Indices Correlated with Red Blood Cell Morphology, Summary
    • The image on the right is a representative field from a peripheral blood smear. What characteristics would describe the red cell distribution curve that you would expect to see?
    • The image on the right is a representative field from a peripheral blood smear. Which of the following MCV values correlates best with the peripheral blood picture?
  • Using indices and RDW to morphologically classify anemias
    • Anemia Defined and Classified
    • Anemia Defined and Classified, continued
    • Morphologic Classification of Anemias
    • Pathophysiologic Classification of Anemias
    • An 18-year-old female has a CBC performed as part of a routine physical exam. The following results are obtained, and the physician determines she is anemic. After reviewing her CBC results, which of the following would be an appropriate description of the anemia?ParameterValueReference IntervalWhite blood cells (WBC)5.6 × 109/L4.0–10.0 x 109/LRed blood cells (RBC)3.2 × 1012/L4.2&#
    • Match each anemia listed below with the mechanism for the anemia.
    • A patient presents with the following measured parameters on the complete blood count:ParameterValueReference IntervalWhite blood cells (WBC)5.6 × 109/L4.0–10.0 × 109/LRed blood cells (RBC)3.6 × 1012/L4.2–5.9 × 1012/LHemoglobin9.2 g/dL12–16 g/dLHematocrit28%37–48%MCV78 fL80–100 fLRDW-CV 16%11.0–15.0%Which statement represents the patient's co
    • The image on the right is a representative field from a peripheral blood smear. What would you expect to see on the automated blood count?
  • The significance of delta checks as it relates to red blood cell indices.
    • Delta Check Alerts Using Red Blood Cell Indices
    • Delta Check Alerts Using Red Blood Cell Indices, continued
    • An automated CBC produced the following parameters:ParameterValueReference IntervalWhite blood cells (WBC)5.6 × 109/L4.0–10.0 × 109/LRed blood cells (RBC)3.4 × 1012/L4.2–5.9 × 1012/LHemoglobin11.1 g/dL12–16 g/dLHematocrit31%37–48%MCV92 fL80–100 fLMCHC 38 g/dL30–37 g/dLA specimen for a repeat CBC is received in the laboratory six hours later.
  • References
    • References

Additional Information

Level of instruction: Intermediate
Intended audience: Medical laboratory scientists, medical laboratory technicians, laboratory supervisors, and laboratory managers. This course is also appropriate for MLS and MLT students and pathology residents.
Author information: Sheryl A. Whitlock, MA. Ed, MLS(ASCP)BB is the owner of ARK Laboratory Consulting, LLC, and works as a technical consultant for various laboratories. Sheryl served as the laboratory coordinator for the Student Health Services Laboratory at the University of Delaware for 15 years. Sheryl received her Master’s degree in Education from Arcadia University in Glenside, Pennsylvania. She has more than 35 years of experience in laboratory science, including management, education, and hands-on bench experience. She has written and published textbooks and laboratory manuals, as well as having contributed to numerous online and print articles in the field of laboratory medicine.
Reviewer information:
Joshua J. Cannon, MS, MLS(ASCP)CMSHCM received his Bachelor of Science and Master of Science in Medical Laboratory Science from Thomas Jefferson University in Philadelphia, PA. He holds Medical Laboratory Scientist and Specialist in Hematology certifications through the ASCP Board of Certification. He was a professor at Thomas Jefferson University for seven years before transitioning into his current role as Education Developer at MediaLab. His areas of expertise and professional passions include clinical hematology and interprofessional education.
Rory Huschka, M.Ed., MLS(ASCP), has over 20 years of experience as a medical technologist, technical supervisor, professor, and manager. He is the former Director of Clinical Laboratory Technology and Medical Laboratory Technician Programs at Brookline College. He is currently a Sales Representative at MediaLab. Rory holds a B.S. degree in Medical Technology from North Dakota State University and an M.S. in Educational Leadership. Rory also holds a certificate in Six Sigma from Villanova University.  
Content information: This course discusses the use of red cell indices and red cell distribution width to describe a population of red blood cells. The course provides information regarding the interpretation of red cell histograms that are part of the automated cell count and correlations between indices, RDWs, and peripheral blood smear observations.